The objective of the proposed program is to demonstrate the feasibility of constructing a single solid state laser system that can emit in the 325nm to 1000nm spectral range for fluorescent diagnostics and photodynamic therapy of gastrointestinal tumors. The proposal will take advantage of a newly developed tunable, solid state, titanium doped sapphire (Ti:Al2O3) vibronic laser. The broad tuning range of the T1Al2O3 laser and the ability to use Nd:Yag laser as a pump source will offer novel opportunities for the diagnosis and treatment of alimentary canal digestive diseases.